CN113214017A - Method for producing fertilizer containing nitrate nitrogen by using secondary guniting process - Google Patents
Method for producing fertilizer containing nitrate nitrogen by using secondary guniting process Download PDFInfo
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- CN113214017A CN113214017A CN202110636481.5A CN202110636481A CN113214017A CN 113214017 A CN113214017 A CN 113214017A CN 202110636481 A CN202110636481 A CN 202110636481A CN 113214017 A CN113214017 A CN 113214017A
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- nitrate
- ammonium
- nitrogen
- urea
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05B—PHOSPHATIC FERTILISERS
- C05B7/00—Fertilisers based essentially on alkali or ammonium orthophosphates
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/40—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting fertiliser dosage or release rate; for affecting solubility
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/80—Soil conditioners
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/10—Solid or semi-solid fertilisers, e.g. powders
- C05G5/12—Granules or flakes
Abstract
The invention discloses a method for producing nitrate nitrogen-containing fertilizer by using a secondary guniting process, which comprises the steps of mixing ammonium phosphate nitrate, byproduct calcium ammonium nitrate, ammonium sulfate and sepiolite powder, feeding the mixture into an extrusion granulator, screening the mixture, feeding the screened mixture into a roller granulator, and spraying concentrated slurry mixed by urea, dilute sulfuric acid, polyvinyl alcohol 1788 and zinc polyaspartate for granulation. Nitrate nitrogen is more than or equal to 5 percent, sulfur element and trace element zinc can reasonably utilize waste resources, the secondary guniting process ensures that the production system has less return material, the production efficiency is greatly improved, the appearance of the product is improved, and the product is not agglomerated and pulverized.
Description
Technical Field
The invention belongs to the technical field of preparation methods of agricultural fertilizers, and particularly relates to a method for producing a nitrate nitrogen-containing fertilizer by using a secondary guniting process.
Background
The execution standard of the urea ammonium nitrogen fertilizer is HG/T4214-2011 urea ammonium nitrogen fertilizer, the urea nitrogen and the ammonium nitrogen are respectively 15 percent, the total nitrogen is 30 percent, and the urea ammonium nitrogen and the urea are mixed and granulated to form the urea ammonium nitrogen fertilizer. The urea ammonium nitrogen fertilizer reduces the activity of soil urease, can reduce the volatilization loss of ammonia, and can be converted into an ammonium nitrogen form under the action of the urease after urea nitrogen is applied to the soil, so that the mineralization speed of urea molecules into the ammonium nitrogen is reduced.
The byproduct calcium ammonium nitrate, which is a large amount of leftovers in pharmaceutical factories, is offwhite powder and is 100 percent soluble in water, has safer and more comprehensive nutrients than commonly used agricultural ammonium nitrate, has small pH value after being applied to soil, can reduce the concentration of active aluminum, reduce the fixation of active phosphorus, cannot cause soil hardening, can loosen the soil, and is popular with farmers. If the by-products of ammonium calcium nitrate, ammonium phosphate nitrate and other raw materials are used as nitrate nitrogen and added into the urea-ammonium nitrogen fertilizer, effective nutrition can be rapidly provided for crops to absorb in the seedling stage of the crops in northwest arid water-deficient areas.
In the process of producing the fertilizer by using the raw materials such as urea, byproduct calcium ammonium nitrate, ammonium phosphate and the like by adopting the traditional roller method, the material has strong hygroscopicity after the urea and the byproduct calcium ammonium nitrate are mixed, the intensity of granulation particles is lower than 20N, the materials are often caused to be large and the granulation cylinder is seriously scabbed, the whole production system has more returned materials, the yield is lower, the production efficiency is low, and the particles are rough and unsmooth; the finished fertilizer is particularly easy to agglomerate and pulverize.
Disclosure of Invention
Aiming at the prior art, the invention provides a method for producing a nitrate nitrogen-containing fertilizer by using a secondary guniting process, which contains nitrate nitrogen, sulfur and zinc elements, can reasonably utilize waste resources, has less returned materials of a production system by using the secondary guniting process, greatly improves the production efficiency, improves the appearance of a product, does not agglomerate and does not pulverize.
The invention is realized by the following technical scheme:
a method for producing fertilizer containing nitrate nitrogen by using secondary spraying process is characterized by that it adopts ammonium phosphate nitrate, by-product calcium ammonium nitrate, ammonium sulfate and sepiolite powder, mixes them, and makes them be fed into extrusion granulating machine, after screening, it is fed into drum granulating machine, and sprays the concentrated slurry mixed by urea, dilute sulfuric acid, polyvinyl alcohol 1788 and polyaspartic acid zinc to make granulation, and the nitrate nitrogen product is greater than or equal to 5%.
Firstly, 200-380 parts of ammonium phosphate nitrate, 200-350 parts of byproduct calcium ammonium nitrate, 350-550 parts of ammonium sulfate and 2-80 parts of sepiolite powder are weighed, mixed and then enter an extrusion granulator, and screened and then enter a roller granulator. The feeding proportion is further preferably 280-350 parts of ammonium phosphate nitrate, 250-300 parts of byproduct calcium ammonium nitrate, 380-450 parts of ammonium sulfate and 5-15 parts of sepiolite powder.
Then, 900-1000 parts of urea, 50 parts of water, 10-50 parts of 60% dilute sulfuric acid, 0.2-5 parts of polyvinyl alcohol 1788 and 0.5-3 parts of zinc polyaspartate are sequentially added into a slurry tank, and stirred for 30 minutes at 90 ℃; after fully mixing, thick slurry is prepared and sprayed into a roller granulator for granulation. The feeding proportion is preferably 930-990 parts of urea, 50 parts of water, 20-45 parts of 60% dilute sulfuric acid, 0.3-0.9 part of polyvinyl alcohol 1788 and 0.8-2.0 parts of zinc polyaspartate.
The invention adopts a process of extrusion granulation and secondary slurry spraying, and the dosage of the concentrated slurry is 25-45% of the total mass of the ammonium phosphate nitrate, the by-products of calcium ammonium nitrate, ammonium sulfate and sepiolite powder, and is further preferably 30-45%.
In the invention, the byproduct calcium ammonium nitrate is leftovers of pharmaceutical factories containing nitrogen, calcium, magnesium and ferrum, and the nutrient composition of the leftovers is that nitrogen is more than or equal to 20 percent, calcium oxide is more than or equal to 4 percent, magnesium oxide is more than or equal to 3 percent, and ferrum is more than or equal to 0.1 percent, wherein nitrate nitrogen is more than or equal to 10 percent, can be completely dissolved in water, and is physiologically neutral.
In the present invention, urea reacts exothermically with dilute sulfuric acid to produce a portion of the urea sulfate component. Mixing with polyvinyl alcohol 1788 and zinc polyaspartate to obtain concentrated slurry, and spraying into a granulator for granulation. The main advantages are: (1) the thick slurry has certain physical permeability and can be tightly adhered to the original extruded particles without falling off. (2) The urea sulfate has a special molecular structure and is 100% quick in water solubility, and the urea sulfate releases nutrients according to the requirements of crops under the drive of beneficial microbial bacteria, and has a controlled release effect compared with urea. (3) Because the operation temperature of the urea sulfate is low, the urea solution does not generate hydrolysis and condensation reaction, and biuret is not generated. (4) The urea sulfate, the polyvinyl alcohol 1788 and the zinc polyaspartate are mixed into thick slurry and sprayed into a granulator for granulation, so that the material viscosity is moderate, the granules are smooth and mellow, and the granule strength is high; the polyvinyl alcohol 1788 and the polyaspartic acid zinc are both high molecular materials, and present a net structure in the thick slurry, so that the rheological property is improved. Spraying urea or urea sulfate solution alone often results in cracking or caking of the particle surface into agglomerates. (5) The concentrated slurry is weakly acidic: the product is particularly suitable for neutral and alkaline soil in northwest, can effectively improve soil and provides a suitable environment for microorganisms. (6) Effectively supplement the sulfur and the trace element zinc.
The invention has the beneficial effects that: mixing ammonium phosphate nitrate, byproduct calcium ammonium nitrate, ammonium sulfate and sepiolite powder, and feeding the mixture into an extrusion granulator, wherein the granule strength after extrusion is high and can reach more than 20N; the concentrated slurry is sprayed into a roller granulator for granulation, the materials in the granulation cylinder are easier to be pelletized, and the pelletizing rate can reach more than 95%; the fertilizer efficiency is superior to that of the common urea ammonium nitrogen fertilizer, and the fertilizer contains nitrate nitrogen and sulfur elements, so that waste resources can be reasonably utilized; the extrusion granulation and secondary spraying process has less material return of the production system, greatly improved production efficiency, improved product appearance, no caking and no pulverization.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The invention aims to overcome the defects in the process of producing the novel urea ammonium nitrogen fertilizer by using the byproduct calcium ammonium nitrate in the prior art, and the method comprises the steps of mixing ammonium phosphate nitrate, the byproduct calcium ammonium nitrate, ammonium sulfate and sepiolite powder, then feeding the mixture into an extrusion granulator, screening the mixture, then feeding the screened mixture into a roller granulator, and spraying concentrated slurry mixed by urea, dilute sulfuric acid, polyvinyl alcohol 1788 and zinc polyaspartate for granulation. .
Example 1:
300 parts of ammonium phosphate nitrate (32-4-0), 280 parts of byproduct calcium ammonium nitrate, 410 parts of ammonium sulfate and 10 parts of sepiolite powder are weighed, mixed and then enter an extrusion granulator, and screened and then enter a roller granulator.
Then 950 parts of urea, 50 parts of water, 35 parts of 60% dilute sulfuric acid, 0.5 part of polyvinyl alcohol 1788 and 1.5 parts of zinc polyaspartate are sequentially added into a slurry tank, and stirred for 30 minutes at 90 ℃; after fully mixing, thick slurry is prepared and sprayed into a roller granulator for granulation.
The dosage of the concentrated slurry is 35.5 percent of the total mass of the ammonium nitrate phosphorus and the byproduct calcium ammonium nitrate, the ammonium sulfate and the sepiolite powder,
the obtained product contains nitrate nitrogen, the nitrate nitrogen is more than or equal to 5 percent, and the urea nitrogen is more than or equal to 11 percent.
Through field fertilizer efficiency tests, the yield of the fertilizer is increased by 9.5 percent compared with the common urea ammonium nitrogen fertilizer under the condition of the same nitrogen content and the same dosage.
Example 2:
firstly, 330 parts of ammonium phosphate nitrate (32-4-0), 260 parts of byproduct calcium ammonium nitrate, 400 parts of ammonium sulfate and 10 parts of sepiolite powder are weighed, mixed and then enter an extrusion granulator, and screened and then enter a roller granulator.
Then 980 parts of urea, 50 parts of water, 38 parts of 60% dilute sulfuric acid, 0.5 part of polyvinyl alcohol 1788 and 1.5 parts of zinc polyaspartate are sequentially added into a slurry tank, and stirred for 30 minutes at 90 ℃; after fully mixing, thick slurry is prepared and sprayed into a roller granulator for granulation.
The dosage of the concentrated slurry is 33.5 percent of the total mass of the ammonium nitrate phosphorus and the byproduct calcium ammonium nitrate, the ammonium sulfate and the sepiolite powder,
the obtained product contains nitrate nitrogen, the nitrate nitrogen is more than or equal to 5 percent, and the urea nitrogen is more than or equal to 11 percent.
Through field fertilizer efficiency tests, the yield of the fertilizer is increased by 10.3 percent compared with the common urea ammonium nitrogen fertilizer under the condition of the same nitrogen content and the same dosage.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (5)
1. A method for producing fertilizer containing nitrate nitrogen by using secondary spraying process is characterized by that it adopts ammonium phosphate nitrate, by-product calcium ammonium nitrate, ammonium sulfate and sepiolite powder, mixes them, and makes them be fed into extrusion granulating machine, after screening, it is fed into drum granulating machine, and sprays the concentrated slurry mixed by urea, dilute sulfuric acid, polyvinyl alcohol 1788 and polyaspartic acid zinc to make granulation, and the nitrate nitrogen product is greater than or equal to 5%.
2. The method for producing the fertilizer containing nitrate nitrogen by using the secondary guniting process as claimed in claim 1, wherein 200-380 parts of ammonium phosphorus nitrate, 200-350 parts of by-product calcium ammonium nitrate, 350-550 parts of ammonium sulfate and 2-80 parts of sepiolite powder are mixed and then enter an extrusion granulator, and the mixture enters a roller granulator after being screened. The feeding proportion is further preferably 280-350 parts of ammonium phosphate nitrate, 250-300 parts of byproduct calcium ammonium nitrate, 380-450 parts of ammonium sulfate and 5-15 parts of sepiolite powder.
3. The method for producing fertilizers containing nitrate nitrogen by using the secondary guniting process as claimed in claim 1, wherein the byproduct calcium ammonium nitrate is leftovers of pharmaceutical factories containing nitrogen, calcium, magnesium and iron, and the nutrient composition of the leftovers is that nitrogen is more than or equal to 20%, calcium oxide is more than or equal to 4%, magnesium oxide is more than or equal to 3%, and iron is more than or equal to 0.1%, wherein nitrate nitrogen is more than or equal to 10%, can be completely dissolved in water, and is physiologically neutral.
4. The method for producing a nitrate nitrogen-containing fertilizer by using the secondary guniting process according to claim 1, wherein 900 to 1000 parts of urea, 50 parts of water, 10 to 50 parts of 60% dilute sulfuric acid, 0.2 to 5 parts of polyvinyl alcohol 1788 and 0.5 to 3 parts of zinc polyaspartate are sequentially added into a slurry tank, and stirred at 90 ℃ for 30 minutes; after fully mixing, thick slurry is prepared and sprayed into a roller granulator for granulation. The feeding proportion is preferably 930-990 parts of urea, 50 parts of water, 20-45 parts of 60% dilute sulfuric acid, 0.3-0.9 part of polyvinyl alcohol 1788 and 0.8-2.0 parts of zinc polyaspartate.
5. The method for producing the fertilizer containing nitrate nitrogen by using the secondary guniting process as claimed in claim 1, wherein the concentrated slurry is sprayed into a granulation cylinder for granulation, and the dosage of the concentrated slurry is 25-45% of the total mass of the ammonium phosphate nitrate, the byproduct calcium ammonium nitrate, the ammonium sulfate and the sepiolite powder, and is further preferably 30-35%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202110636481.5A CN113214017A (en) | 2021-06-08 | 2021-06-08 | Method for producing fertilizer containing nitrate nitrogen by using secondary guniting process |
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| CN202110636481.5A CN113214017A (en) | 2021-06-08 | 2021-06-08 | Method for producing fertilizer containing nitrate nitrogen by using secondary guniting process |
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| CN111018627A (en) * | 2020-03-01 | 2020-04-17 | 郑州大学 | Composite fertilizer containing polymorphic nitrogen and manufacturing method thereof |
-
2021
- 2021-06-08 CN CN202110636481.5A patent/CN113214017A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101613244A (en) * | 2009-08-07 | 2009-12-30 | 中国-阿拉伯化肥有限公司 | A kind of method that improves granulation performance of urine-based fertilizer |
| CN102503622A (en) * | 2011-09-17 | 2012-06-20 | 山东金山化肥有限公司 | Process for producing urea sulfate ammoniated compound fertilizer |
| CN103193548A (en) * | 2013-05-03 | 2013-07-10 | 辽宁施壮肥业有限公司 | Organic-inorganic multi-element pollution-free compound fertilizer and preparation method thereof |
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| CN111018627A (en) * | 2020-03-01 | 2020-04-17 | 郑州大学 | Composite fertilizer containing polymorphic nitrogen and manufacturing method thereof |
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Application publication date: 20210806 |